Crusher devices such as impact crushers, roller presses, grinding devices or mill devices may be fed material to crush or grind to a smaller size. Examples of an impact crusher, for instance, may be appreciated from U.S. Pat. Nos. 5,890,666 and 7,293,725. Impact crushers may have curtains, or plates that are positioned to impact material to crush material fed to the impact crusher. Examples of crusher devices, such as for example, jaw crushers, impact crushers, vertical impact crushers, horizontal impact crushers or gyratory crushers may also be appreciated from U.S. Pat. Nos. 6,932,289, 6,637,680, 6,375,105, 5,971,306, 5,833,153, 5,323,974, 4,927,089, 4,398,674, 3,976,255, 3,918,648, 3,847,358, 3,315,902, and 2,588,180 and U.S. Patent Application Publication No. 2010/0147985.
During operation of a crusher device, some material that may be fed to the device may be very difficult or impossible for the device to crush. For instance, an uncrushable element such as tramp material may pass through a crusher device. As another example, the uncrushable element may be material that is much harder than the crusher device is designed for crushing. When such uncrushable material is positioned between crushing bodies of a crusher device, the crusher device may experience substantially high pressure. Such high pressure may create problems for the crusher device. For instance, the high pressure can damage the crusher device or may increase the rate of wear experienced by the crusher device. If the crusher device has a hydraulic system, such high pressure may also damage that hydraulic system or increase the wear experienced by components of the hydraulic system.
A new crusher device is needed. Preferably, the new crusher device is configured to permit uncrushable elements to pass through the device quickly to minimize the damage or wear the device may experience while the uncrushable element passes through the device.